Air filter arrangement; assembly; and, methods

ABSTRACT

An air filter media construction or arrangement is disclosed. The air filter media construction or arrangement includes media comprising opposite inlet and outlet flow faces, with a perimeter housing seal. Also described are serviceable filter cartridges and air cleaners including the filter cartridges. Methods of assembly and use are also provided.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation filing of U.S. Ser. No.14/838,486, filed Aug. 28, 2015, which has issued as U.S. Pat. No.9,937,455. U.S. Ser. No. 14/838,486 is a continuation of U.S. Ser. No.13/936,518, filed Jul. 8, 2013, which issued as U.S. Pat. No. 9,120,047on Sep. 1, 2015. U.S. Ser. No. 13/936,518 is a continuation of U.S. Ser.No. 13/268,016, filed Oct. 7, 2011, and which issued as U.S. Pat. No.8,480,779 on Jul. 9, 2013. U.S. Ser. No. 13/268,016 is a continuationfiling of U.S. Ser. No. 11/629,429, filed Dec. 3, 2007, and which issuedas U.S. Pat. No. 8,034,145 on Oct. 11, 2011. U.S. Ser. No. 11/629,429 isa US filing of PCT/US2005/020593 and includes, with some edits, thedisclosure of U.S. application 60/579,754 filed Jun. 14, 2004. A rightof priority to the filing of U.S. Ser. Nos. 14/838,486; 13/936,518;13/268,016; 11/629,429; PCT/US2005/020593; and, application 60/579,754is claimed, to the extent appropriate. The entire disclosures of U.S.Ser. Nos. 14/838,486; 13/936,518; 13/268,016; 11/629,429;PCT/US2005/020593; and, application 60/579,754 are incorporated hereinby reference.

FIELD OF THE DISCLOSURE

The present disclosure relates to filter media for use in filteringgases. The disclosure particularly relates to media packs that usez-filter media which comprises a corrugated media sheet secured tofacing sheet, formed into a media pack. More specifically, thedisclosure relates to such media packs and their inclusion inserviceable filter cartridge arrangements, typically for use in aircleaners. Air cleaner arrangements and methods of assembly and use arealso described.

BACKGROUND

Fluid streams, such as air, can carry contaminant material therein. Inmany instances, it is desired to filter some or all of the contaminantmaterial from the fluid stream. For example, air flow streams to engines(for example combustion air) for motorized vehicles or for powergeneration equipment, gas streams to gas turbine systems and air streamsto various combustion furnaces, carry particulate contaminant thereinthat should be filtered. It is preferred for such systems, that selectedcontaminant material be removed from (or have its level reduced in) thefluid. A variety of fluid filter (air or liquid filter) arrangementshave been developed for contaminant rejection. However, continuedimprovements are sought.

SUMMARY

According to the present disclosure, features useable in preferredfilter cartridges, such as air filter cartridges are provided. Thefeatures can be used together to provide a preferred filter cartridge,however some advantageous cartridges can be constructed to use onlyselected ones of the features. In addition, methods of construction anduse are provided.

In one aspect of the present disclosure, a preferred media pack isprovided, for use in or as air filter cartridges. The media packcomprises a stacked z-filter arrangement having opposite flow faces andopposite sides. At the opposite sides, ends of stacked strips aresecured in, and sealed by, molded end pieces. Preferably the molded endpieces comprise molded polyurethane.

In one example arrangement, the stacked z-filter media pack arrangementcomprises a slanted stacked z-filter media pack arrangement.

Also according to the present disclosure there is provided a filtercartridge which includes a stacked z-filter arrangement. A filtercartridge depicted also comprises a preform in which the media pack ispositioned. The preform preferably comprises four sides and a perimeterseal arrangement. Although alternatives are possible, the perimeter sealarrangement is depicted as an intermediary arrangement, between upstreamand downstream ends of the preform.

The perimeter seal arrangement of the preform may be an obliquearrangement as characterized herein. The perimeter seal arrangement maycomprise a seal member positioned over a projection integral with aremainder portion of the preform. The preform is preferably a moldedcomponent. Preferably the media pack is sealed in the preform, mostpreferably permanently.

Various preferred features for a preform and a filter cartridge, for adescribed type of application, are shown.

Also according to the present disclosure an air cleaner arrangementutilizing a preferred filter cartridge as described, is provided. Theair cleaner arrangement generally comprises a housing having twosections, separable from one another and configured to engage a sealarrangement of the filter cartridge therebetween, when assembled andsecured to one another. Example features for the housing arrangement areprovided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a fragmentary, schematic, perspective view of z-filter mediauseable in arrangements according to the present disclosure.

FIG. 2 is an enlarged schematic, cross-sectional view of a portion ofthe media depicted in FIG. 1.

FIG. 3 is a schematic view of examples of various corrugated mediadefinitions.

FIG. 4 is a schematic view of a process for manufacturing mediaaccording to the present disclosure.

FIG. 5 is a cross-sectional view of an optional end dart for mediaflutes useable in arrangements according to the present disclosure.

FIG. 6 is a schematic depiction of a step of creating a blocked, stackedz-filter media pack.

FIG. 6A is a schematic perspective view of a slanted stacked z-filtermedia pack arrangement.

FIG. 6B is a schematic cross-sectional view of a mold operation forforming a portion of the media arrangement.

FIG. 7 is a schematic top inlet end perspective view of a filtercartridge including a z-filter media pack according to FIG. 6A therein.

FIG. 8 is a schematic top outlet end perspective view of the filtercartridge of FIG. 7.

FIG. 8A is a schematic bottom outlet end perspective view of the filtercartridge of FIG. 8.

FIG. 8B is a side elevational view of a filter cartridge depicted inFIG. 7.

FIG. 9 is a top plan view of an air cleaner arrangement including afilter cartridge according to FIGS. 7-8B therein.

FIG. 10 is a cross-sectional view taken along line 10-10, FIG. 9.

DETAILED DESCRIPTION I. Z-Filter Media Configurations, Generally

Fluted filter media can be used to provide fluid filter constructions ina variety of manners. One well known manner is as a z-filterconstruction. The term “z-filter construction” as used herein, is meantto refer to a filter construction in which individual ones ofcorrugated, folded or otherwise formed filter flutes are used to definesets of longitudinal, typically parallel, inlet and outlet filter flutesfor fluid flow through the media; the fluid flowing along the length ofthe flutes between opposite inlet and outlet flow ends (or flow faces)of the media. Some examples of z-filter media are provided in U.S. Pat.Nos. 5,820,646; 5,772,883; 5,902,364; 5,792,247; 5,895,574; 6,210,469;6,190,432; 6,350,296; 6,179,890; 6,235,195; Des. 399,944; Des. 428,128;Des. 396,098; Des. 398,046; and, Des. 437,401; each of these fifteencited references being incorporated herein by reference.

One type of z-filter media, utilizes two specific media componentsjoined together, to form the media construction. The two components are:(1) a fluted (typically corrugated) media sheet; and, (2) a facing mediasheet. The facing media sheet is typically non-corrugated, however itcan be corrugated, for example perpendicularly to the flute direction asdescribed in U.S. provisional 60/543,804, filed Feb. 11, 2004,incorporated herein by reference.

The fluted (typically corrugated) media sheet and the facing media sheettogether, are used to define media having parallel inlet and outletflutes. In some instances, the fluted sheet and facing sheet are securedtogether and are then coiled to form a z-filter media construction. Sucharrangements are described, for example, in U.S. Pat. Nos. 6,235,195 and6,179,890, each of which is incorporated herein by reference. In certainother arrangements, some non-coiled sections of corrugated media securedto facing media, are stacked on one another, to create a filterconstruction. An example of this is described in FIG. 11 of U.S. Pat.No. 5,820,646, incorporated herein by reference.

Typically, coiling of the fluted sheet/facing sheet combination arounditself, to create a coiled media pack, is conducted with the facingsheet directed outwardly. Some techniques for coiling are described inU.S. provisional application 60/467,521, filed May 2, 2003 and PCTApplication US 04/07927, filed Mar. 17, 2004, now published as WO04/082795, each of which is incorporated herein by reference. Theresulting coiled arrangement generally has, as the outer surface of themedia pack, a portion of the facing sheet, as a result.

The term “corrugated” used herein to refer to structure in media, ismeant to refer to a flute structure resulting from passing the mediabetween two corrugation rollers, i.e., into a nip or bite between tworollers, each of which has surface features appropriate to cause acorrugation affect in the resulting media. The term “corrugation” is notmeant to refer to flutes that are formed by techniques not involvingpassage of media into a bite between corrugation rollers. However, theterm “corrugated” is meant to apply even if the media is furthermodified or deformed after corrugation, for example by the foldingtechniques described in PCT WO 04/007054, published Jan. 22, 2004,incorporated herein by reference.

Corrugated media is a specific form of fluted media. Fluted media ismedia which has individual flutes (for example formed by corrugating orfolding) extending thereacross.

Serviceable filter element or filter cartridge configurations utilizingz-filter media are sometimes referred to as “straight through flowconfigurations” or by variants thereof. In general, in this context whatis meant is that the serviceable filter elements generally have an inletflow end (or face) and an opposite exit flow end (or face), with flowentering and exiting the filter cartridge in generally the same straightthrough direction. The term “serviceable” in this context is meant torefer to a media containing filter cartridge that is periodicallyremoved and replaced from a corresponding fluid (e.g. air) cleaner. Insome instances, each of the inlet flow end and outlet flow end will begenerally flat or planar, with the two parallel to one another. However,variations from this, for example non-planar faces, are possible.

A straight through flow configuration (especially for a coiled mediapack) is, for example, in contrast to serviceable filter cartridges suchas cylindrical pleated filter cartridges of the type shown in U.S. Pat.No. 6,039,778, incorporated herein by reference, in which the flowgenerally makes a turn as its passes through the serviceable cartridge.That is, in a U.S. Pat. No. 6,039,778 filter, the flow enters thecylindrical filter cartridge through a cylindrical side, and then turnsto exit through an end face (in forward-flow systems). In a typicalreverse-flow system, the flow enters the serviceable cylindricalcartridge through an end face and then turns to exit through a side ofthe cylindrical filter cartridge. An example of such a reverse-flowsystem is shown in U.S. Pat. No. 5,613,992, incorporated by referenceherein.

The term “z-filter media construction” and variants thereof as usedherein, without more, is meant to refer to any or all of: a web ofcorrugated or otherwise fluted media secured to (facing) media withappropriate sealing to allow for definition of inlet and outlet flutes;or, a media pack constructed or formed from such media into a threedimensional network of inlet and outlet flutes; and/or, a filtercartridge or construction including such a media pack.

In FIG. 1, an example of media 1 useable in z-filter media is shown. Themedia 1 is formed from a corrugated sheet 3 and a facing sheet 4.

In general, the corrugated sheet 3, FIG. 1 is of a type generallycharacterized herein as having a regular, curved, wave pattern of flutesor corrugations 7. The term “wave pattern” in this context, is meant torefer to a flute or corrugated pattern of alternating troughs 7 b andridges 7 a. The term “regular” in this context is meant to refer to thefact that the pairs of troughs and ridges (7 b, 7 a) alternate withgenerally the same repeating corrugation (or flute) shape and size.(Also, typically in a regular configuration each trough 7 b issubstantially an inverse of each ridge 7 a.) The term “regular” is thusmeant to indicate that the corrugation (or flute) pattern comprisestroughs and ridges with each pair (comprising an adjacent trough andridge) repeating, without substantial modification in size and shape ofthe corrugations along at least 70% of the length of the flutes. Theterm “substantial” in this context, refers to a modification resultingfrom a change in the process or form used to create the corrugated orfluted sheet, as opposed to minor variations from the fact that themedia sheet 3 is flexible. With respect to the characterization of arepeating pattern, it is not meant that in any given filterconstruction, an equal number of ridges and troughs is necessarilypresent. The media 1 could be terminated, for example, between a paircomprising a ridge and a trough, or partially along a pair comprising aridge and a trough. (For example, in FIG. 1 the media 1 depicted infragmentary has eight complete ridges 7 a and seven complete troughs 7b.) Also, the opposite flute ends (ends of the troughs and ridges) mayvary from one another. Such variations in ends are disregarded in thesedefinitions, unless specifically stated. That is, variations in the endsof flutes are intended to be covered by the above definitions.

In the context of the characterization of a “curved” wave pattern ofcorrugations, the term “curved” is meant to refer to a corrugationpattern that is not the result of a folded or creased shape provided tothe media, but rather the apex 7 a of each ridge and the bottom 7 b ofeach trough is formed along a radiused curve. A typical radius for suchz-filter media would be at least 0.25 mm and typically would be not morethan 3 mm.

An additional characteristic of the particular regular, curved, wavepattern depicted in FIG. 1, for the corrugated sheet 3, is that atapproximately a midpoint 30 between each trough and each adjacent ridge,along most of the length of the flutes 7, is located a transition regionwhere the curvature inverts. For example, viewing back side or face 3 a,FIG. 1, trough 7 b is a concave region, and ridge 7 a is a convexregion. Of course when viewed toward front side or face 3 b, trough 7 bof side 3 a forms a ridge; and, ridge 7 a of face 3 a, forms a trough.(In some instances, region 30 can be a straight segment, instead of apoint, with curvature inverting at ends of the segment 30.)

A characteristic of the particular regular, curved, wave patterncorrugated sheet 3 shown in FIG. 1, is that the individual corrugationsare generally straight. By “straight” in this context, it is meant thatthrough at least 70%, typically at least 80% of the length between edges8 and 9, the ridges 7 a and troughs 7 b do not change substantially incross-section. The term “straight” in reference to corrugation patternshown in FIG. 1, in part distinguishes the pattern from the taperedflutes of corrugated media described in FIG. 1 of WO 97/40918 and PCTPublication WO 03/47722, published Jun. 12, 2003, incorporated herein byreference. The tapered flutes of FIG. 1 of WO 97/40918, for example,would be a curved wave pattern, but not a “regular” pattern, or apattern of straight flutes, as the terms are used herein.

Referring to the present FIG. 1 and as referenced above, the media 1 hasfirst and second opposite edges 8 and 9. When the media 1 is coiled andformed into a media pack, in general edge 9 will form an inlet end forthe media pack and edge 8 an outlet end, although an oppositeorientation is possible.

Adjacent edge 8 is provided a sealant bead 10, sealing the corrugatedsheet 3 and the facing sheet 4 together. Bead 10 will sometimes bereferred to as a “single facer” bead, since it is a bead between thecorrugated sheet 3 and facing sheet 4, which forms the single facer ormedia strip 1. Sealant bead 10 seals closed individual flutes 11adjacent edge 8, to passage of air therefrom.

Adjacent edge 9, is provided seal bead 14. Seal bead 14 generally closesflutes 15 to passage of unfiltered fluid therein, adjacent edge 9. Bead14 would typically be applied as strips of the media 1 are secured toone another during stacking. Thus bead 14 will form a seal between aback side 17 of facing sheet 4, and side 18 of the next adjacentcorrugated sheet 3. When the media 1 is cut in strips and stacked,instead of coiled, bead 14 is referenced as a “stacking bead.” (Whenbead 14 is used in a coiled arrangement, not depicted herein, it isreferenced as a “winding bead.”)

Referring to FIG. 1, once the media 1 is incorporated into a media pack,for example by stacking, it can be operated as follows. First, air inthe direction of arrows 12, would enter open flutes 11 adjacent end 9.Due to the closure at end 8, by bead 10, the air would pass through themedia, for example as shown by arrows 13. It could then exit the mediapack, by passage through open ends 15 a of the flutes 15, adjacent end 8of the media pack. Of course operation could be conducted with air flowin the opposite direction.

For the particular arrangement shown herein in FIG. 1, the parallelcorrugations 7 a, 7 b are generally straight completely across themedia, from edge 8 to edge 9. Straight flutes or corrugations can bedeformed or folded at selected locations, especially at ends.Modifications at flute ends for closure are generally disregarded in theabove definitions of “regular,” “curved” and “wave pattern.”

Z-filter constructions which do not utilize straight, regular curvedwave pattern corrugation shapes are known. For example in Yamada et al.U.S. Pat. No. 5,562,825 corrugation patterns which utilize somewhatsemicircular (in cross section) inlet flutes adjacent narrow V-shaped(with curved sides) exit flutes are shown (see FIGS. 1 and 3, of U.S.Pat. No. 5,562,825). In Matsumoto, et al. U.S. Pat. No. 5,049,326circular (in cross-section) or tubular flutes defined by one sheethaving half tubes attached to another sheet having half tubes, with flatregions between the resulting parallel, straight, flutes are shown, seeFIG. 2 of Matsumoto '326. In Ishii, et al. U.S. Pat. No. 4,925,561(FIG. 1) flutes folded to have a rectangular cross section are shown, inwhich the flutes taper along their lengths. In WO 97/40918 (FIG. 1),flutes or parallel corrugations which have a curved, wave patterns (fromadjacent curved convex and concave troughs) but which taper along theirlengths (and thus are not straight) are shown. Also, in WO 97/40918flutes which have curved wave patterns, but with different sized ridgesand troughs, are shown.

In general, the filter media is a relatively flexible material,typically a non-woven fibrous material (of cellulose fibers, syntheticfibers or both) often including a resin therein, sometimes treated withadditional materials. Thus, it can be conformed or configured into thevarious corrugated patterns, without unacceptable media damage. Also, itcan be readily coiled or otherwise configured for use, again withoutunacceptable media damage. Of course, it must be of a nature such thatit will maintain the required corrugated configuration, during use.

In the corrugation process, an inelastic deformation is caused to themedia. This prevents the media from returning to its original shape.However, once the tension is released the flute or corrugations willtend to spring back, recovering only a portion of the stretch andbending that has occurred. The facing sheet is sometimes tacked to thefluted sheet, to inhibit this spring back in the corrugated sheet. Suchtacking is shown at 20.

Also, typically, the media contains a resin. During the corrugationprocess, the media can be heated to above the glass transition point ofthe resin. When the resin then cools, it will help to maintain thefluted shapes.

The media of the corrugated sheet 3 facing sheet 4 or both, can beprovided with a fine fiber material on one or both sides thereof, forexample in accord with U.S. Pat. No. 6,673,136, incorporated herein byreference.

An issue with respect to z-filter constructions relates to closing ofthe individual flute ends. Although alternatives are possible, typicallya sealant or adhesive is provided, to accomplish the closure. As isapparent from the discussion above, in typical z-filter media,especially that which uses straight flutes as opposed to tapered flutes,large sealant surface areas (and volume) at both the upstream end andthe downstream end are needed. High quality seals at these locations arecritical to proper operation of the media structure that results. Thehigh sealant volume and area, creates issues with respect to this.

Attention is now directed to FIG. 2, in which a z-filter mediaconstruction 40 utilizing a regular, curved, wave pattern corrugatedsheet 43, and a non-corrugated flat sheet 44, is depicted. The distanceD1, between points 50 and 51, defines the extension of flat media 44 inregion 52 underneath a given corrugated flute 53. The length D2 of thearcuate media for the corrugated flute 53, over the same distance D1 isof course larger than D1, due to the shape of the corrugated flute 53.For a typical regular shaped media used in fluted filter applications,the linear length D2 of the media 53 between points 50 and 51 will oftenbe at least 1.2 times D1. Typically, D2 would be within a range of1.2-2.0, inclusive. One particularly convenient arrangement for airfilters has a configuration in which D2 is about 1.25-1.35×D1. Suchmedia has, for example, been used commercially in Donaldson Powercore™Z-filter arrangements. Herein the ratio D2/D1 will sometimes becharacterized as the flute/flat ratio or media draw for the corrugatedmedia.

In the corrugated cardboard industry, various standard flutes have beendefined. For example the standard E flute, standard X flute, standard Bflute, standard C flute and standard A flute. FIG. 3, attached, incombination with Table A below provides definitions of these flutes.

Donaldson Company, Inc., (DCI) the assignee of the present disclosure,has used variations of the standard A and standard B flutes, in avariety of z-filter arrangements. These flutes are also defined in TableA and FIG. 3.

TABLE A (Flute definitions for FIG. 3) DCI A Flute/flat = 1.52:1; TheRadii (R) are as follows: Flute: R1000 = .0675 inch (1.715 mm); R1001 =.0581 inch (1.476 mm); R1002 = .0575 inch (1.461 mm); R1003 = .0681 inch(1.730 mm); DCI B Flute/flat = 1.32:1; The Radii (R) are as follows:Flute: R1004 = .0600 inch (1.524 mm); R1005 = .0520 inch (1.321 mm);R1006 = .0500 inch (1.270 mm); R1007 = .0620 inch (1.575 mm); Std. EFlute/flat = 1.24:1; The Radii (R) are as follows: Flute: R1008 = .0200inch (.508 mm); R1009 = .0300 inch (.762 mm); R1010 = .0100 inch (.254mm); R1011 = .0400 inch (1.016 mm); Std. X Flute/flat = 1.29:1; TheRadii (R) are as follows: Flute: R1012 = .0250 inch (.635 mm); R1013 =.0150 inch (.381 mm); Std. B Flute/flat = 1.29:1; The Radii (R) are asfollows: Flute: R1014 = .0410 inch (1.041 mm); R1015 = .0310 inch (.7874mm); R1016 = .0310 inch (.7874 mm); Std. C Flute/flat = 1.46:1; TheRadii (R) are as follows: Flute: R1017 = .0720 inch (1.829 mm); R1018 =.0620 inch (1.575 mm); Std. A Flute/flat = 1.53:1; The Radii (R) are asfollows: Flute: R1019 = .0720 inch (1.829 mm); R1020 = .0620 inch (1.575mm).

Of course other, standard, flutes definitions from the corrugated boxindustry are known.

In general, standard flute configurations from the corrugated boxindustry can be used to define corrugation shapes or approximatecorrugation shapes for corrugated media. Comparisons above between theDCI A flute and DCI B flute, and the corrugation industry standard A andstandard B flutes, indicate some convenient variations.

II. Manufacture of Stacked Media Configurations Using Fluted Media,Generally

A. Overview of Process; Option of Darting Flutes

In FIG. 4, one example of a manufacturing process for making a mediastrip corresponding to strip 1, FIG. 1 is shown. In general, facingsheet 64 and the fluted (corrugated) sheet 66 having flutes 68 arebrought together to form a media web 69, with an adhesive bead locatedtherebetween at 70. The adhesive bead 70 will form a single facer bead14, FIG. 1. An optional darting process occurs at station 71 to formcenter darted section 72 located mid-web. The z-filter media or Z-mediastrip 74 can be cut or slit at 75 along the bead 70 to create two pieces76, 77 of z-filter media 74, each of which has an edge with a strip ofsealant (single facer bead) extending between the corrugating and facingsheet. Of course, if the optional darting process is used, the edge witha strip of sealant (single facer bead) would also have a set of flutesdarted at this location. The strips or pieces 76, 77 can then be cutacross, for stacking, as described below in connection with FIG. 6.

Techniques for conducting a process as characterized with respect toFIG. 4 are described in PCT WO 04/007054, published Jan. 22, 2004incorporated herein by reference.

Still in reference to FIG. 4, before the z-filter media 74 is putthrough the darting station 71 the media 74 must be formed. In theschematic shown in FIG. 4, this is done by passing a flat sheet of media92 through a pair of corrugation rollers 94, 95. In the schematic shownin FIG. 4, the flat sheet of media 92 is unrolled from a roll 96, woundaround tension rollers 98, and then passed through a nip or bite 102between the corrugation rollers 94, 95. The corrugation rollers 94, 95have teeth 104 that will give the general desired shape of thecorrugations after the flat sheet 92 passes through the nip 102. Afterpassing through the nip 102, the flat sheet 92 becomes corrugated and isreferenced at 66 as the corrugated sheet. The corrugated sheet 66 isthen secured to facing sheet 64. (The corrugation process may involveheating the media, in some instances.)

Still in reference to FIG. 4, the process also shows the facing sheet 64being routed to the darting process station 71. The facing sheet 64 isdepicted as being stored on a roll 106 and then directed to thecorrugated sheet 66 to form the Z-media 74. The corrugated sheet 66 andthe facing sheet 64 are secured together by adhesive or by other means(for example by sonic welding).

Referring to FIG. 4, an adhesive line 70 is shown used to securecorrugated sheet 66 and facing sheet 64 together, as the sealant bead.Alternatively, the sealant bead for forming the facing bead could beapplied as shown as 70 a. If the sealant is applied at 70 a, it may bedesirable to put a gap in the corrugation roller 95, and possibly inboth corrugation rollers 94, 95, to accommodate the bead 70 a.

The type of corrugation provided to the corrugated media is a matter ofchoice, and will be dictated by the corrugation or corrugation teeth ofthe corrugation rollers 94, 95. One preferred corrugation pattern willbe a regular curved wave pattern corrugation, of straight flutes, asdefined herein above. A typical regular curved wave pattern used, wouldbe one in which the distance D2, as defined above, in a corrugatedpattern is at least 1.2 times the distance D1 as defined above. In onepreferred application, typically D2=1.25-1.35×D1. In some instances thetechniques may be applied with curved wave patterns that are not“regular,” including, for example, ones that do not use straight flutes.

As described, the process shown in FIG. 4 can be used to create thecenter darted section 72. FIG. 5 shows, in cross-section, one of theflutes 68 after darting and slitting.

A fold arrangement 118 can be seen to form a darted flute 120 with fourcreases 121 a, 121 b, 121 c, 121 d. The fold arrangement 118 includes aflat first layer or portion 122 that is secured to the facing sheet 64.A second layer or portion 124 is shown pressed against the first layeror portion 122. The second layer or portion 124 is preferably formedfrom folding opposite outer ends 126, 127 of the first layer or portion122.

Still referring to FIG. 5, two of the folds or creases 121 a, 121 b willgenerally be referred to herein as “upper, inwardly directed” folds orcreases. The term “upper” in this context is meant to indicate that thecreases lie on an upper portion of the entire fold 120, when the fold120 is viewed in the orientation of FIG. 5. The term “inwardly directed”is meant to refer to the fact that the fold line or crease line of eachcrease 121 a, 121 b, is directed toward the other.

In FIG. 5, creases 121 c, 121 d, will generally be referred to herein as“lower, outwardly directed” creases. The term “lower” in this contextrefers to the fact that the creases 121 c, 121 d are not located on thetop as are creases 121 a, 121 b, in the orientation of FIG. 5. The term“outwardly directed” is meant to indicate that the fold lines of thecreases 121 c, 121 d are directed away from one another.

The terms “upper” and “lower” as used in this context are meantspecifically to refer to the fold 120, when viewed from the orientationof FIG. 5. That is, they are not meant to be otherwise indicative ofdirection when the fold 120 is oriented in an actual product for use.

Based upon these characterizations and review of FIG. 5, it can be seenthat a preferred regular fold arrangement 118 according to FIG. 5 inthis disclosure is one which includes at least two “upper, inwardlydirected, creases.” These inwardly directed creases are unique and helpprovide an overall arrangement in which the folding does not cause asignificant encroachment on adjacent flutes.

A third layer or portion 128 can also be seen pressed against the secondlayer or portion 124. The third layer or portion 128 is formed byfolding from opposite inner ends 130, 131 of the third layer 128.

Another way of viewing the fold arrangement 118 is in reference to thegeometry of alternating ridges and troughs of the corrugated sheet 66.The first layer or portion 122 is formed from an inverted ridge. Thesecond layer or portion 124 corresponds to a double peak (afterinverting the ridge) that is folded toward, and in preferredarrangements, folded against the inverted ridge.

Techniques for providing the optional dart described in connection withFIG. 5, in a preferred manner, are described in PCT WO 04/007054,incorporated herein by reference. Other techniques for media managementare described in PCT application US 04/07927, filed Mar. 17, 2004,incorporated herein by reference.

Techniques described herein are well adapted for use of media packs thatresult from arrangements that, instead of being formed by coiling, areformed from a plurality of strips of single facer.

Opposite flow ends or flow faces of the media pack can be provided witha variety of different definitions. In many arrangements, the ends aregenerally flat and perpendicular to one another.

The flute seals (single facer bead, winding bead or stacking bead) canbe formed from a variety of materials. In various ones of the cited andincorporated references, hot melt or polyurethane seals are described aspossible for various applications. These are useable for applicationsdescribed herein.

In FIG. 6, schematically there is shown a step of forming a stackedz-filter media pack from strips of z-filter media. Referring to FIG. 6,strip 200 is being shown added to a stack 201 of strips 202 analogous tostrip 200. Strip 200 can be cut from either of strips 76, 77, FIG. 4. At205, FIG. 6, application of a stacking bead 206 is shown, between eachlayer corresponding to a strip 200, 202 at an opposite edge from thesingle facer bead or seal. (Stacking can also be done with each layerbeing added to the bottom of the stack, as opposed to the top.)

Referring to FIG. 6, each strip 200, 202 has front and rear edges 207,208 and opposite side edges 209 a, 209 b. Inlet and outlet flutes of thecorrugated sheet/facing sheet combination comprising each strip 200, 202generally extend between the front and rear edges 207, 208, and parallelto side edges 209 a, 209 b.

Still referring to FIG. 6, in the media pack 201 being formed, oppositeflow faces are indicated at 210, 211. The selection of which one offaces 210, 211 is the inlet end face and which is the outlet end face,during filtering, is a matter of choice. In some instances the stackingbead 206 is preferably positioned adjacent the upstream or inlet face211. The flow faces 210, 211, extend between opposite side faces 220,221.

The stacked media pack 201 being formed in FIG. 6, is sometimes referredto herein as a “blocked” stacked media pack. The term “blocked” in thiscontext, is an indication that the arrangement is formed to arectangular block in which all faces are 90° relative to all adjoiningwall faces. Alternate configurations are possible, as discussed below inconnection with FIG. 6A and certain of the remaining figures.

In some instances, media pack 201 will be referenced as having aparallelogram shape in any cross-section, meaning that any two oppositeside faces extend generally parallel to one another.

It is noted that a blocked, stacked arrangement corresponding to FIG. 6is described in the prior art of U.S. Pat. No. 5,820,646, incorporatedherein by reference. It is also noted that stacked arrangements aredescribed in U.S. Pat. Nos. 5,772,883; 5,792,247; U.S. Provisional60/457,255 filed Mar. 25, 2003; and U.S. Ser. No. 10/731,564 filed Dec.8, 2003. All four of these latter references are incorporated herein byreference. It is noted that the stacked arrangement at FIG. 6 of U.S.Ser. No. 10/731,504, is a slanted stacked arrangement.

III. Air Cleaner Arrangements Including Stacked Z-Filter Media Pack

A. End Seal Arrangements for Stacked Z-Filter Media Packs.

Herein above, flute seal arrangements for z-filter media are discussed.Flute seals are generally the seal that are provided between thecorrugated sheet and the facing sheet (the single facer bead or seal);and, the seal provided between strips in the z-filter media pack (thestacker bead).

Referring to FIG. 6, opposite side edges 209 a, 209 b of the variousstrips (200, 201) also need to be sealed against leakage. The sealing ingeneral should be at two locations:

-   -   1. Between the single facer sheet and the corrugated sheet, for        each strip or layer (200, 202); and    -   2. Between the various strips or layers (200, 202).

The reason seals are preferred at these locations is to inhibitunfiltered air from reaching a downstream portion of an air cleanerarrangement, in which the media pack 201 is used.

Herein, an approach toward provision of side edge seals in stacked mediapack is provided. It will be understood by reference to FIG. 6A.

Referring to FIG. 6A, a z-filter media pack 250 is depicted,schematically, comprising strips 251 of z-filter media (corrugatedsheet/facing sheet combinations) stacked on one another. Along sideedges 252, 253, of the stack of strips 251, seals are required, as notedabove.

At side edge 252 an end piece 255 is depicted; and, at side edge 253 ananalogous end piece 256 is depicted. The end pieces 255, 256 have theside edges of the various strips 251 secured thereto. Thus, the endpieces 255, 256 can provide side edge seals for single facer strips 251.

Preferably the end pieces 255, 256 are molded with the associated sideedges or ends of the strips 251 embedded therein, during molding, toprovide the seals. Typically the molded end pieces 255, 256 are moldedfrom polyurethane. Typically and preferably a foamed polyurethane isused. Although alternatives are possible, one form of useable foamedpolyurethane is one which is molded to an as-molded density of nogreater than 30 lbs/cu.ft. (0.48 g/cc), sometimes no greater than 15lbs/cu.ft. (0.24 g/cc), and in some instances no greater than 10lbs/cu.ft. (0.16 g/cc). Although alternatives are possible, in manyinstances the end pieces 255, 256 will be molded to a hardness, Shore A,of no greater than 30, typically no greater than 25, and often 20 orless, for example 12 to 20. Harder, more dense, materials can be used,but they are not preferred, in some instances, for weight and costsavings.

It is noted that end pieces analogous to end pieces 255, 256 (exceptrectangular) can be used for the blocked stacked arrangement 201, FIG.6. However the particular example 250 depicted in FIG. 6A, rather thanbeing a blocked stacked arrangement, is a slanted stacked arrangement;the term “slanted” in this context, being meant to indicate that theopposite flow surfaces 260, 261 do not extend perpendicular to sidesurfaces 265, 266; the surfaces 265, 266 corresponding to the surfacesacross which flutes of the z-filter media pack 250 extend.

Typically and preferably surfaces 260, 261 are parallel to one anotherand, in overall feature, each is planar. It is noted that each surface260, 261 actually comprises edges of individual strips stepped from oneanother, and thus each is not smooth; however in general these mediaedges will define a planar surface. Thus, the media stack of media pack250 has a parallelogram shape.

Typically and preferably an acute angle A, referred to herein as theacute slant angle, between one of surfaces 265, 266 and an adjacent oneof surfaces 260, 261 is at least 30°, typically within the range of30-70°, when the media pack is not a blocked, stacked, arrangement. Insome arrangements an angle of about 40-50°, such as 45°, is used. Forthe particular embodiments described herein below in connection withFIGS. 7 and 8, the acute angle A is preferably within the range of about50°-70°, for example about 60°.

Still referring to FIG. 6A, for the particular media pack 250 depicted,edges 270, 271 of end piece 255 extend parallel to one another, as docorresponding edges 272, 273 of end piece 256. Alternatives arepossible.

Attention is directed to mold stand off indent arrangement 275 in endpiece 255. An analogous stand off would be found in end piece 256 aswell. Stand off indent arrangement 275 is an artifact from a method usedto mold the end piece of FIG. 6A. In particular it represents a locationin which a mold used to mold piece 255 included a raised portion toengage and support the media ends above a bottom of the mold, duringmolding. Although not required, it is noted that in some moldingoperations, the portion of the mold that forms region 276 may be sunkenor lower relative to the portion of the molds region 278, as well, toadvantage. If this latter is practiced, region 276 will be thicker thanregion 278.

Attention is now directed to FIG. 6B, which is a schematic, fragmentarycross-sectional view is shown of a molding operation for forming endpiece 255. Referring to FIG. 6B, a mold arrangement is indicated at 280,and a media pack is indicated at 281, inserted into the mold forformation of end piece 255, FIG. 6A. At 282, the mold stand offarrangement is shown, against which the media pack 282 would bepositioned, within the mold cavity 283. Stand offs 282 will result inthe artifact 275, FIG. 6A, in the molded end piece. Resin would cure inregions 286, 287, to cause molding. For the particular arrangement,region 287 is deeper than region 286, for molding advantage relating tothe amount of flash that might undesirably extend over surfaces 265, 266during molding. The media pack 281 can be pinched by the mold, ifdesired, to control resin flow/rise.

B. A Filter Cartridge Including a Stacked Z-Filter Media Pack and anOuter Preform.

Reference numeral 300, FIG. 7, depicts a filter cartridge or mediaconstruction according to the present disclosure. The filter cartridge300 comprises a media pack 303 contained within a frame piece 304. Inuse, the filter cartridge 300 would be installed in an air cleanerhousing, for example as described below. Typically and preferably theframe piece 304 comprises a single, integral, molded frame piece, with aseal member secured thereto, as described below. By “single, integral”in this context, it is meant that piece 304, except for the seal addedthereto, is structurally one piece, formed as an integral piece, forexample from a molded plastic, such as a glass filled nylon.

Still referring to FIG. 7, media pack 303, shown schematically,typically and preferably comprises a stacked z-filter media arrangement310, for example as described above in connection with FIGS. 6 and 6A.The stacked media pack arrangement 310 is positioned within interior 304a of frame piece 304 with a media pack inlet flow face 312 positionedaligned with and adjacent open inlet flow end 313 of frame piece 304;and, as seen in FIG. 8, with an outlet flow face 320 positioned alignedwith an adjacent opposite open outlet flow end 321 of frame piece 304.The z-filter media pack 310, then, is positioned with inlet and outletflutes extending generally between opposite, open, flow faces 312 and320, FIGS. 7 and 8. (In FIGS. 7, 8 and 8A the media pack is depictedschematically and detail of the flutes is not shown.)

It is noted that the particular filter cartridge 300 depicted in FIGS. 7and 8 is constructed to utilize a slanted stacked z-filter media pack310 a, in particular media pack 250, FIG. 6A. This is preferred for theparticular housing, described below in connection with FIGS. 9-14, inwhich the cartridge 300 is to be positioned in use. However, cartridge300 could be configured to use alternate stacked arrangements, forexample a blocked stacked z-filter media pack arrangement, or a slantedstacked arrangement with a different acute slant angle, for othersystems and arrangements.

Referring again to FIG. 7, at 330 a housing seal arrangement isdepicted. Herein, the term “housing seal” and variants thereof refer toa seal arrangement on filter cartridge 300, positioned to form a sealwith an air cleaner housing, in use. The housing seal arrangement 330shown includes seal material thereon positioned to releasably sealagainst one or more frame pieces of housing sections, when installed.This will be understood by reference to FIGS. 9-10 below. Althoughalternatives are possible, the particular seal arrangement 330 depictedis an axial pinch seal, 330 a. The term “axial” when used in thiscontext, is meant to refer to a seal that operates under compressiveforces directed generally in the direction of double headed arrow 332,FIG. 7; i.e., in the direction of extension of the inlet and outletflutes between opposite media pack flow faces 312, 320. For theparticular arrangement 300 depicted, the “axial” direction is adirection through the media pack 303, in a direction of inlet and outletflow flutes from open flow end 313 to open flow end 321 of frame piece304.

The particular housing seal arrangement 330 depicted, comprises a rigidextension 335 surrounding a remainder 336 of frame piece 304, with asheath 338 of seal mounted thereon, FIG. 10. The sheath 338 maycomprise, for example, a pre-molded neoprene piece having a troughtherein, for fitting over extension 335. The preferred rigid extension335, sometimes called a rigid perimeter projection, would generally havea shape corresponding to sheath 338, and be integrally molded as aremainder of frame piece 304. The sheath 338 would typically beseparately added, as a premolded flexible sheath with a groove forreceiving extension 335 therein. In some systems sheath 338 may bemolded directly to rigid extension 335. In typical applications,however, sheath 338 would be performed and be secured after frame piece304 had been preformed, using an adhesive or similar connection.

Referring again to FIG. 7, for the particular filter cartridge 300depicted, the frame piece 304 has a generally rectangular cross-section,taken perpendicularly to the axial directions indicated by double headedarrow 332, and includes first and second opposite (upper and lower)surface panels 340, 341 and first and second opposite sides 342, 343.Although alternatives are possible, as indicated previously frame piece304 has a generally rectangular cross-section when taken perpendicularlyto arrows 332, thus the angle between any two adjacent sides, takenperpendicularly to axial lines 332, is 90°. Panels 340, 341 and sides342, 343 are sometimes collectively referenced herein as a side wallstructure for frame piece 304.

Interior 304 a may taper downwardly in size in extension between end 313and end 321, for example as a result of a draft angle of 0.2°-0.5°, formolding of frame piece 304. This can be used to help pinch the mediapack 303 in position, adjacent end 321.

It is noted that the particular perimeter seal arrangement 330 depicted,is an intermediate perimeter seal arrangement 330 b, meaning it ispositioned in frame piece 304 at an intermediate location spaced betweenflow ends 313 and 321. In alternate arrangements, the seal arrangement330 could be positioned adjacent one or the other of the ends 313, 321,depending upon the particular housing arrangement involved.

Referring to FIG. 7, for the particular embodiment depicted, panel 340includes sections 340 a and 340 b. Section 340 a is positioned in framepiece 304 upstream of the housing seal arrangement 330, and section 340b is positioned in frame piece 304 downstream of the housing sealarrangement 330.

Similarly, panel 341, FIG. 8A, has a first section 341 a in frame piece304 upstream of the housing seal arrangement 330, and a section 341 b inframe piece 304 downstream of the housing seal arrangement 330.

Side panel 342, FIG. 8, has sections 342 a and 342 b positioned in framepiece 304 on opposite sides of housing seal arrangement 330, withsection 342 a being upstream and section 342 b being downstream. Finallyside section 343, FIG. 8A, has section 343 a positioned in frame piece304 upstream of housing seal arrangement 330, and section 343 bpositioned in frame piece 304 downstream of housing seal arrangement330.

In general, panel and side sections (340 a, 341 a, 342 a and 343 a)positioned upstream of the housing seal arrangement 330 are in anenvironment on the “dirty air” side of the housing seal arrangement 330,in use. Thus, in use panel sections 340 a, 341 a, 342 a and 343 a arepreferably solid and have no apertures therein, so that the only accessof unfiltered air flow to media pack 303 is through inlet flow face 312,FIG. 7. Collectively, sections 340 a, 341 a, 342 a and 343 a aresometimes referred to herein, as an upstream side wall structure orsection 304 b of frame piece 304.

The requirements with respect to sections 340 b, 341 b, 342 b and 343 b,on the downstream side of housing seal arrangements 330, on the otherhand, are different. Here, the region surrounding cartridge 300 isexposed to the clean air plenum, and thus apertures can be provided inthe sections 340 b, 341 b, 342 b, 343 b. In the arrangement shown,apertures are indicated, as examples, at 345. Herein, sections 340 b,341 b, 342 b and 343 b collectively, are sometimes referred to herein asa downstream side wall structure or section 304 c, FIG. 7, of framepiece 304.

Apertures 345 provide for weight saving and a cost savings. Weight andcost savings result from the fact that less resin material is needed fordrain piece 304. In typical arrangements using apertures 345, each panelsection with apertures therein will be at least 20% open (in area),typically at least 40%, usually 50% or more. The particular shapes toapertures 345 can be selected for ornamentation.

Attention is now directed to lip 346, FIG. 7, which comprises a flange347 around end 313 of the frame piece 304. Flange 347 provides a framearound the media pack 303, into which an end sealant can be placed. Theend sealant positioned within the flange 347, between the media pack 303and the frame piece 304, will secure media pack 303 within frame piece304 and will prevent unfiltered air from passing between the media pack303 and the frame piece 304 during use. The flange 347 does not need tobe larger than to accommodate a frame of sealant around inlet flow face312 against the frame piece 304. A flange providing a gap within therange of 2-10 mm outwardly from the media pack 303, over an axialextension or depth within the range of about 4-20 mm will be sufficient.

Attention is now directed to FIG. 8, in particular to end 321 of framepiece 304. It is noted that end 321 is open, except for cross-pieces 350therein, extending between panel 340, 341. Cross pieces 350 provide agrid arrangement across downstream face 351 of media pack 303, and thussupport the media pack 303 at the downstream face 351 during bothassembly and use. Preferably the cross-pieces 350 extend perpendicularto individual single facer layers 251, FIG. 6A, in the media pack 303.

During assembly, the cross pieces 350 operate as a grid system 350 a toproperly position the media pack 303 when it is inserted through end313. During operation, the cross-pieces 350 operate as a grid system 350a to inhibit deformation of the media pack 305 under air pressureagainst inlet face 312.

Referring to FIGS. 7 and 8, again housing seal arrangement 330 is of atype generally referred to herein as a perimeter seal 330 b. By the term“perimeter” in this context, it is meant that the seal arrangement 330extends completely around the z-filter media construction, includingmedia pack 303 or, alternately stated in this instance, around aperimeter of frame piece 304. Although alternatives are possible, theparticular housing seal arrangement 330 depicted, with respect to ends313, 321 is an intermediate seal 330 c. Again by the term “intermediate”in this context, it is meant the seal arrangement 330 is positionedspaced between opposite ends 313, 321 of the frame piece 304, and it isnot adjacent either one of those ends.

Also, although alternatives are possible, the particular sealarrangement 330 depicted, does not rest entirely in a planeperpendicular to the axial direction indicated by arrows 332. Rather theseal arrangement 300 is in a plane oblique to the axial direction of theframe piece 304. Such a seal arrangement will generally be referred toas an oblique perimeter seal arrangement 330 d. The particular obliqueseal arrangement 330 d provided, is positioned to extend perpendicularlyto the axial direction 332, in its direction extension across panels340, 341, but at a non-perpendicular angle to the axial direction, inextension across the side panels 342, 343. The acute angle B, FIG. 8, ofextension across the panels 342, 343 relative to the axial direction 332is, for example, within the range of 30° to 80°, typically 35° to 60°,although alternatives are possible.

It is noted that the particular oblique perimeter seal depicted, for ahousing seal 330, extends at an acute angle B relative to the axialdirection 332 (FIG. 8) which is different than an angle A of extensionof the flow faces 312, 320, although alternatives are possible. For theparticular example shown, the acute angle B relative to the axialdirection, of the housing seal arrangement 330, in extension acrosspanels 342, 343, is smaller than the acute angle A (FIG. 6A) ofextension of faces 312, 313 versus the axial direction 332.

Referring to FIGS. 7 and 8, it is noted that in extension across panels340, 341, projection 335 also extends outwardly from panel 340, 341 atan oblique, i.e., non-perpendicular, angle C, FIG. 8. Althoughalternatives are possible, this will be preferred for certainarrangements. The oblique angle C may be the same as angle B, but suchis not required in all examples.

In FIG. 8B, a side elevational view of cartridge 300 depicted, withcertain example angles and dimensions designated as follows:

AA=28.0 mm; BB=135.0 mm; CC=15°; DD=28.0 mm; EE=293.4 mm.

The dimensions depicted in FIG. 8B are for example only, and variationsare possible within the scope of the current disclosure.

C. An Example Air Cleaner Arrangement, FIGS. 9,10.

In FIGS. 9, 10 an example air cleaner arrangement useable for a filtercartridge arrangement (or z-filter media construction) according toFIGS. 7 and 8 is depicted. It is noted that a variety of differenthousing arrangements are possible, the one depicted in FIGS. 9, 10 beingan example. With respect to the housing, the filter cartridge is aserviceable component, i.e., it is removable for replacement after use.

Attention is first directed to FIG. 9 in which housing 375 is depicted.The housing 375 comprises separable sections 376, 377, secured togetherby latches 380. The housing 375 can comprise molded plastic, althoughalternatives are possible.

Section 376 comprises an inlet section having air flow inlet 383therein. Mounted over inlet 383 is flexible, collapsible, bellows 384.

Section 377 is an outlet section including air flow outlet 386, throughwhich filtered air leaves air cleaner housing 375 to be directed todownstream engine components.

Housing section 376 includes a perimeter flange 389; and housing section377 includes perimeter flange 390. Flanges 389 and 390 are configured toengage one another with housing seal arrangement 330 of an internallyreceived filter cartridge corresponding to cartridge 303, FIGS. 7 and 8,therebetween. In general the housing 375 is configured to internallyreceive upstream frame section 340 a, FIG. 7, within housing section376; and, to internally receive downstream frame section 340 b withinhousing section 377.

Referring to FIG. 10, a side cross-sectional view, the particularhousing 375 depicted, is configured to be mounted in the generalorientation shown in FIG. 10, with bellows 384 directed upwardly,although alternative housing configurations are possible. The relativelylow vertical relief depicted in FIG. 10 is convenient, for mounting theair cleaner 375 in small spaces under the hood of truck, for example onthe engine. Mount arrangement 396, FIG. 10, can be used to accomplishthis.

In FIG. 10, a bottom of housing 375 is viewable. Referring to FIG. 10,it is noted that mount arrangement 396 is mounted only on section 377,with no portion thereof on section 376. This means that when installed,section 376 can be moved relative to section 377, while section 377remains anchored in place in equipment in which housing 375 isinstalled, for example a truck. The movement of section 376 isconvenient, to facilitate service access to an internally receivedfilter cartridge.

Referring to FIG. 9, at 397 an air conduit for communication with an airintake for a compressor equipment is shown. At 398, a port for arestriction indicator is depicted.

Also, a water ejector port and valve arrangement (not shown) could beincluded in section 376. The water ejector port and valve arrangementwould typically be positioned to point downwardly, when the housing 375,is installed, and to be upstream from an internally received filtercartridge. (An example water ejector port and valve arrangement isdepicted at 395, in the parent U.S. Provisional Application Ser. No.60/579,754, filed Jun. 14, 2004.)

Comparing FIGS. 9 and 10, it is noted that housing 375 is configured toengage oblique perimeter housing seal arrangement 330 positioned withthe seal portion extending across upper face or side 375 a of thehousing 375 being further from the bellows 384 and inlet 383, than theportion of the housing seal arrangement 330 extending across lowerhousing face or side 375 b. This is convenient for servicing. Thehousing has opposite ends, FIGS. 9, at 375 x and 375 y, with faces 375a, 375 b extending therebetween. In extension across face 375 a, thehousing seal arrangement 330 is closer to end 3′75 y, than it is to end375 x. In the context of FIG. 10, the terms “upper” and “lower,” inreference to surfaces 375 a and 375 b, is meant to be in reference tothe orientation shown. The installation orientation might be different.

Referring again to FIG. 9, it is noted that corners 389 a, 389 b offlange 389 each comprise a hanger arrangement sized to engagecorresponding portions of flange 390 on housing section 377. This willfacilitate assembly. In particular, the hangers 389 a, 389 b will helpposition section 376 on section 377, without relative movement orslippage while the latches 380 are being operated.

In FIG. 9, through inlet aperture 383, one can view a location of theupstream face 312 of the media pack 303. Thus, it can be seen that airdirected into inlet aperture 383 does not need to make a complete 90°turn, to begin to encounter the inlet face 315 of the media pack 303.

Although alternatives are possible, disregarding the mountingarrangement 396, the housing for the arrangement depicted,cross-sectional height H1, FIG. 10, is no more than 50% of the width W1,FIG. 9; and, typically no more than 35% of the width W1. Althoughalternatives are possible, for the typical frame piece 304, the internalheight (not including the housing seal arrangement 330 and mount 396) isgenerally no more than 50% of the cross-sectional width, typically nomore than 30% of the cross-sectional width.

Although alternatives are possible, an example media pack 303 useable inthe described filter cartridge 300 and housing 375, is one having: awidth of 18-26 inches (45.7-66 cm), typically 20-24 in. (50.8-61 cm); aheight of 3-10 inches (6.7-25.4 cm), typically 4-6 in. (10.1-15.2 cm);and, a depth (flute length) of about 6-10 in. (15.2-25.4 cm), typically7-9 in. (17.8-22.9 cm).

What is claimed:
 1. An air filter cartridge comprising: (a) a mediaarrangement comprising filter media; (b) first and second, opposite,molded side pieces having the media extending therebetween; (c) aperimeter housing seal comprising an axial pinch seal; (i) the perimeterhousing seal having a first sealing surface, for sealing engagement witha housing during use; (d) the air filter cartridge: including an inletflow end and an outlet flow end; and, having a rectangularcross-section, at an intermediate location between the flow ends, in adirection perpendicular to a direction between the inlet and outlet flowends; (i) the first and second, opposite, side pieces each having adownstream edge adjacent the outlet flow end that does not extendperpendicular to a direction of air flow through the filter cartridgeduring filtering; and, (ii) the first sealing surface faces in adirection toward the outlet flow end; (A) the first sealing surfacehaving a portion, extending across the first molded side piece, thatextends non-parallel to the downstream edge of the first molded sidepiece; and, (B) the first sealing surface having a portion, extendingacross the second molded side piece, that extends non-parallel to thedownstream edge of the second molded side piece.
 2. An air filtercartridge according to claim 1 wherein: (a) the filter media extends, ina direction between the flow ends, at least 6 inches.
 3. An air filtercartridge according to claim 1 wherein: (a) the filter media extends, ina direction between the flow ends, 6-10 inches.
 4. An air filtercartridge according to claim 1 wherein: (a) the first sealing surfaceextends, in a direction of extension between the first and second endpieces, along a direction perpendicular to a flow direction between theinlet and outlet flow ends.
 5. An air filter cartridge according toclaim 1 wherein: (a) the media at the intermediate portion has arectangular cross-sectional shape having a height of no more than 50% ofa width; the width being in a direction between the first and second endpieces and the height being perpendicular to the width.
 6. An air filtercartridge according to claim 5 wherein: (a) the media intermediateportion has a rectangular cross-sectional shape having a height of nomore than 35% of the width.
 7. An air filter cartridge according toclaim 1 wherein: (a) the first and second, opposite, molded side piecesare molded with media embedded therein.
 8. An air filter cartridgeaccording to claim 1 wherein: (a) the axial pinch seal ismolded-in-place.
 9. An air filter cartridge according to claim 8wherein: (a) the axial pinch seal is molded-in-place on a seal supportthat extends around the media.
 10. An air filter cartridge according toclaim 1 wherein: (a) the cartridge includes planar inlet and outlet flowends.
 11. An air filter cartridge according to claim 10 wherein: (a) theplanar inlet and outlet flow ends extend parallel to one another.
 12. Anair filter cartridge according to claim 1 wherein: (a) the inlet andoutlet flow ends extend parallel to one another.
 13. An air filtercartridge according to claim 1 wherein: (a) the perimeter housing sealarrangement is an intermediate axial pinch seal.
 14. An air filtercartridge according to claim 1 wherein: (a) the first and second,opposite, molded side pieces are spaced from, and separately moldedfrom, one another.
 15. An air filter cartridge according to claim 1including: (a) a grid arrangement extending across the outlet flow end.16. An air filter cartridge according to claim 1 wherein: (a) the mediaarrangement comprises flutes extending in a direction between the inletflow end and the outlet flow end.
 17. An air filter cartridge accordingto claim 16 wherein: (a) the media arrangement comprises a stack ofstrips of filter media; each strip comprising fluted media secured tofacing media.
 18. An air filter cartridge according to claim 1 wherein:(a) the stack of strips comprises a slanted stack having a parallelogramshape with an acute slant angle.
 19. An air filter cartridge accordingto claim 1 wherein: (a) the perimeter housing seal is a slanted sealarrangement extending at an acute slant angle, to an axial directionbetween the opposite flow faces, within the range of 30° to 80°inclusive.
 20. An air cleaner arrangement comprising: (a) a housingdefining an interior and first and second separable sections; (i) thefirst section comprising an air flow inlet section having an air flowinlet therein; and, (ii) the second section comprising an air flowoutlet section having an air flow outlet therein; (b) an air filtercartridge operably positioned within the housing; the air filtercartridge comprising: (i) a media arrangement comprising filter media;(ii) first and second, opposite, molded side pieces having the mediaextending therebetween; (A) a perimeter housing seal comprising an axialpinch seal; (1) the perimeter housing seal having a first sealingsurface, for sealing engagement with a housing during use; (iii) the airfilter cartridge: including an inlet flow end and an outlet flow end;and, having a rectangular cross-section, at an intermediate locationbetween the flow ends, in a direction perpendicular to a directionbetween the inlet and outlet flow ends; (A) the first and second,opposite, side pieces each having a downstream edge adjacent the outletflow end that does not extend perpendicular to a direction of air flowthrough the filter cartridge during filtering; and, (B) the firstsealing surface faces in a direction toward the outlet flow end; (1) thefirst sealing surface having a portion, extending across the firstmolded side piece, that extends non-parallel to the downstream edge ofthe first molded side piece; and, (2) the first sealing surface having aportion, extending across the second molded side piece, that extendsnon-parallel to the downstream edge of the second molded side piece.